No, its not, pardon and the closely linked power of clemency are common powers in representative democracies, often situated with the chief of state or the head of government (in the US, and other Presidential systems, the President is both), or sometimes the cabinet instead of the head of government in a parliamentary or semi-parliamentary system (in some cases, one or the other is assigned by law to a subordinate bureaucracy rather than being HoS/cabinet discretion, as is the case with pardon but not clemency in Canada.) It is generally more used in the US than other Western states, in part because the US has a much harsher criminal justice system with much longer sentences and much weaker provisions for relief other than executive pardon than other systems, but the power itself is common. [0]

The way it is used under Trump is wildly abnormal (for the US or the other representative democracies), though.

[0] see, e.g., https://www.seattletimes.com/nation-world/pardon-power-is-co... ; https://en.wikipedia.org/wiki/Pardon ; etc.